Wednesday, January 10, 2007

The Unity of Consciousness

The Unity of ConsciousnessI have maintained that a key feature of rational inference is that it is inference that must be performed by an agent who possesses a unified consciousness. The idea is that if the self-same entity does not think the premises and think the conclusion, then we have no rational inference. If Dennis has the thought “All men are mortal,” and Bill has the thought “Socrates is a man, and I have the thought “Socrates is mortal,” then none of us have preformed a rational inference.

Now, I have quoted some naturalistic thinkers, such as Blackmore and Pinker (and Dennett seems also to be in this category) who deny the unity of consciousness. The unity is the result of some sort of a user illusion. But if the unity is an illusion, isn’t the inference as well? Or so I would have thought.

Perhaps I can begin discussing the argument by seeing how it appears in Immanuel Kant. Kant seemed to perceive this as a successful argument against materialism but not as an argument in favor of a simple soul, and this is because his own solution to these philosophical problems was to rely on a distinction between the self as it appears to us and the self as it is in itself. But Kant develops the argument as follows:

Every composite substance is an aggregate of several substances, and the action of a composite, or whatever inheres in it as thus composite, is an aggregate of several actions or accidents, distributed among the plurality of substances. Now an effect which arises from the concurrence of many acting substances is indeed possible, namely, when this effect is external only (as, for instance, the motion of a body is the combined motion of all its parts). But with thoughts, as internal accidents belonging to a thinking being, it is different. For suppose it be the composite For suppose it be the composite that thinks: then every part of it would be part of the thought, and only all of them taken together would be the whole thought. But this cannot consistently be maintained. For representations (for instance, the single words of a verse), distributed among different beings, never make up a whole thought (a verse), and it is therefore impossible that a thought should inhere in what is essentially composite. It is therefore possible only in a single substance, which, not being an aggregate of many, is absolutely simple.

William Hasker, the argument’s chief contemporary architect, has a version of the argument that has been formalized as follows:

1. I am aware of my present visual field as a unity; in other words, the various components of the field are experienced by a single subject simultaneously.2. Only something that functions as a whole rather than as a system of parts could experience a visual field as a unity.3. Therefore, the subject functions as a whole rather than as a system of parts.4. The brain and nervous system, and the entire body, is nothing more than a collection of physical parts organized in a certain way. (In other words, holism is false.)5. Therefore, the brain and nervous system cannot function as a whole; it must function as a system of parts.

6. Therefore the subject is not the brain and nervous system (or the body, etc.).7. If the subject is not the brain and nervous system then it is (or contains as a proper part) a non-physical mind or “soul”; that is, a mind that is not ontologically reducible to the sorts of entities studied in the physical sciences. Such a mind, even if it is extended in space, could function as a whole rather than as a system of parts and so could be aware of my present visual field as a unity.8. Therefore, the subject is a soul, or contains a soul as a part of itself.

Now people on the Internet Infidels Discussion Board have been trying to persuade me that my brain can experience my visual field, or the diachronic experience of rational inference, as a unity. The brain, they say, is closely interconnected functionally, and has billions (and billions) of neurons. But I guess I just have to ask them whether they think holism is true, or not. Are physical systems the sum of their parts. If so, then the properties of the “whole” have to be summative properties of the parts. Tell me where all the red bricks are, and even without using the word wall, I can know that there is a wall over there. The properties of the wall are entailed by the properties of the bricks. Wallness is a summative property of bricks. Intentionality and the unity of consciousness do not seem to be entailed after you add up all the properties of the proper parts of the brain. This will be controversial, but I’m prepared to argue that if you add up all the physical states of a person, you could still end up with a zombie.

P. S. David asked where the Kant and Hasker passages came from with respect to the unity of consciousness argument, and I realized that I had forgotten to reference this. The Kant passage is from the Second Paralogism of the Critique of Pure Reason (Kemp Smith translation, St. Martin's) p. 335. The formal argument was generated by Paul Draper (who I think does not endorse it) but it encapsulates the argument as Hasker develops it in The Emergent Self, (New York: Cornell Universitiy Press, 1999), pp. 122-146.

5 Comments:

Victor writes: "Tell me where all the red bricks are, and even without using the word wall, I can know that there is a wall over there. The properties of the wall are entailed by the properties of the bricks."

There is, of course, a second part to this argument.

It is, on the face of it, silly to claim that a brick wall is entirely composed of not-bricks. Yet we now know that a brick itself is entirely composed of not-brick entities, just as a wall is entirely composed of not-wall entities.

At one level of composition, then, a (presumed to exist for sake of argument) brick wall is clearly composed of at least some bricks. At a more fundamental level of composition, though, the brick wall is clearly composed entirely of not-bricks (because even its bricks are themselves composed of not-bricks.)

Consequently, it should be admitted (as I always have admitted, though curiously this admission on my part is commonly ignored by our opponents) that it is not necessarily nonsensical to claim that a brick wall is entirely composed of not-bricks.

This claim, in itself, is _not_ the problem I have with this claim.

Analogically speaking, this is my problem:

a.) I find that all walls, whenever they want to be taken seriously _as_ walls (especially when they are making truth claims, including claims of moral truth), tacitly or explicitly (often explicitly) claim to be _brick_ walls: to be walls which are composed at least partly of brick.

b.) Some of these walls also make one of the following claims of truth: either the ultimate, irreducibly foundational fact of reality, upon which their own composition (as brick walls) is based, is definitely not-brick in its foundationally identifying property; or else that the descriptions of 'brick/not-brick' are so nebulous that there is no point speaking of this Independent Fact in such terms at all.

This is not yet my problem, btw.

c.) Even these walls, however, agree that at least sometimes a (definite) lack of brick-ness in the behavior of a wall results in unreliable claims of truth. For instance, I find that they are especially fond of claiming such a lack of brick-ness in the specific behavior of other walls making claims that the IF has brick-ness as a foundationally identifying property. This purported lack of brick-ness is specifically _why_ they reject their opponents' claim of truth about the brick-ness of the IF; or, relatedly, they explain the rise and persistance of such incorrect beliefs as being a result of lack of brick in those opponent walls, or perhaps faulty brick, or at least insufficient brick.

d.) I am quite prepared in principle to agree with them, that truth claims insufficiently founded on brick should not be accepted--even if the walls in question happen to be on my own side of the aisle (so to speak). Furthermore, I am quite aware that many of the walls on my own side of the aisle not only have insufficient brick for their truth claims, but that they also have a (highly annoying) habit of verbally disdaining the use of brick at all in their claims about the IF (including the brick-ness of the IF).

e.) I do, however, reserve the same right to reject insufficiently bricked truth claims--on exactly the same principle.

f.) The particular walls whom I've been discussing, are meanwhile claiming to me that the IF upon which my (and their) own bricked behaviors are based, either is fundamentally not-brick, or else there's no point discussing such properties at all in regard to the foundational grounds of our own brick-ness.

g.) Consequently, these walls are telling me that in their own particular cases:

g1.) not-brickness has led to brick-ness (while remaining foundationally not-brick);

g2.) or else they themselves are actually not-brick walls (appearances to the contrary), though their own truth claims can and should be regarded as acceptable anyway;

g3.) or else that although it's pointless to discuss brick/not-brick in regard to the grounds of our brickness, the distinction of brick/not-brick can be made clearly enough at least to reject truth-claims (such as the IF having brick-ness) for being insufficiently bricked.

In regard to g3, I can only reply that this looks more than a little over-convenient. If the distinction doesn't hold when discussing the grounds of our brickness, why does it hold when they dismiss a truth-claim as being insufficiently bricked?

In regard to g2 and g1, I ask: since we know that at least sometimes not-brickness leads only to more not-brickness, and since we agree that insufficient brickness is at least sometimes ground for our rejection of a truth claim; then on what ground am I supposed to accept that the claims of these walls can be possibly reliable now?

Will proponents g1 through g3 answer by sheer ungrounded assertion? Or will they answer "Because..."?

If they answer by sheer ungrounded assertion--then (dropping my analogy) I literally have no reason to believe their own truth-claims: and we _agree_ that if I have insufficient reason to believe something, then I should not believe it. ('No reason' seems sufficiently insufficient to me. {g} As it does to them, at least sometimes.)

If they answer with _any_ attempt at a grounding 'because' (regardless of subsequent details)--then they are presuming the answer to the question, in order to answer the question. They are presuming that their own truth claims can be possibly reliable, in order to explain how their own truth claims can be possibly reliable.

And this is something they _have to do_, sooner or later: because the particular claims they are making not only introduce scepticism on the topic, they agree that at least sometimes (or even in the overwhelming majority of cases) it is _proper_ to be sceptical about the accuracy of truth-claims given such conditions _which they say are fundamental to ALL claims of truth_.

No atheist (or intrinsic agnostic) will agree that Christianity is true, for instance, based on sheerly ungrounded Christian assertions. On the contrary, they hold such assertions against such acceptance.

I am not aware of any atheist (or intrinsic agnostic) who would agree that Chrisitanity is true, for instance, because Christian belief is fundamentally a series of automatic reactions to stimuli. I am not aware of any such person who would accept such a truth-claim set, even if it could be proven that Christians (for instance) are exceptionally efficient at such knee-jerk behaviors. I am not aware of any such person who would even for a moment entertain the thought that Christianity (for instance) might be true _on such grounds_. On the contrary, is it not intensely obvious that such people use the attribution of such grounds to _reject_ the truth-claims of their opponents?

What then _should_ I believe, when they tell me that _all_ claims of truth are ungrounded assertions, and/or else are _all_ fundamentally a series of automatic reactions to stimuli?

Yet it is impossible to claim atheism (whether naturalistic or supernaturalistic) without entailing that all truth-claims (including the ones being made by atheists as atheists) are fundamentally a series of automatic reactions to stimuli--even if they go on to propose (which not all atheists do) that in such-n-such complex arrangements the automatic non-intentive reactions and counterreactions, produce intentive behaviors (i.e. become _actions_).

Thus I conclude, that atheism should be deducted out of the option list. I should conclude not-atheism to be true.

(Unless the same argument zorches not-atheism, too. {g} But that's a further story...)

Egads. Don't take this personally, but reading these convoluted philosophical arguments makes me SOOOO glad I left philosophy for neuroscience!!!

On to the philosophy. Looking at the beginning of the argument:

1. [...]the various components of the field are experienced by a single subject simultaneously.

I will grant this for purposes of argument. It resonates with my folk psychology. It does seem that people attribute experiences distributed over space and time to someone, namely, themselves, and (except in pathological cases) not others.

2. Only something that functions as a whole rather than as a system of parts could experience a visual field as a unity.

Before looking at the rest, it is crucial for me to understand the meaning of the terms in this premise.

What is it for something to function as a whole? Does a nutcracker function as a whole? The braking system of a car? Do there exist examples from science of things acting as wholes rather than the sum of their parts? I can ask the same question of what it means for something to function as a system of parts. What does that mean? Canonical examples are much more helpful than lengthy definitions...

By the way, a nice blog. I am an atheist, naturalist, neuroscientist, but find discussions of the unity of consciousness very interesting. I have seen it used to support quantum theories of mind (yuck!), but never non naturalism! Interesting.

Right on Victor. I think you have hold of a valid and important insight. I suspect that you will have a hard time getting cognitive scientists to hear what you're saying though.

There's just one thing I don't think you have quite right, with respect to points 4 and 5 of your argument. If we imagine that the brain can be adequately described by classical physics, your whole argument stands and I agree that it is inescapable although many people will try to convince you that lots of 're-entrant connections' or 'complexity' or 'self-representation' or 'chaotic nonlinear attractor dynamics' will somehow give you the unity you demand. Don't be intimidated by their jargon--they change shapes like Proteus but they can't wiggle out of your argument!

In physics one says that a classical model is 'local,' meaning the behavior of any whole is entirely determined by small or infinitesimal parts and their interactions with immediate neighbors. But we've known classical physics is wrong for about a hundred years. In modern physics, that is quantum physics, spatially separated entities can be in immediate, instantaneous causal contact (as in the famours Aspect nonlocality experiments). Moreover, in quantum systems, a particular global configuration of parts can effectively change what the parts are and the basic rules under which they operate (as in a superconductor).

So I'm saying in classical physics holism is false. In quantum physics, holism is true. The reductionists themselves proved that holism is true!

This line of thinking really is a dangerous idea to a lot of people, so a lot of people try hard not to see it.

I don't know if this will seem disappointing to you, if you thought you had a proof of a non-physical soul. But if something can have effects in the physical world, we may prefer to call it physical, even if it may require 'new physics' to describe. I expect the truth, or the fundamental reality, to be one; so I don't expect to find any contradictions between true religion and true science. I see greater potential for constructing the bridge between science and religion in modern physics because it allows us to (somewhat) naturalize consciousness, and also because it gives us a way to think rationally about how 'infinite quantities' and 'global properties of the cosmos' can influence local finite beings.

I'm the one who has tried to convince Blue Devil Knight that the unity of consciousness implies a quantum brain. He may be disappointed to hear me talking about infinite beings. Anyway, some of our debate about the unity of consciousness is at:http://forebrain.blogspot.com/2005/03/functionalism-and-its-discontents.html

About Me

I am the author of C. S. Lewis's Dangerous Idea: In Defense of the Argument from Reason, published by Inter-Varsity Press. I received a Ph.D in philosophy from the University of Illinois at Urbana-Champaign in 1989.